Converting Auto to manual?

[Philip]

Probably cost an arm and a leg, but is anyone able to give a price on doing this conversion including parts and labour?

it is something I'm pondering on although I absolutely love the NSX I bought earlier this year, it is an auto and I prefer a manual box. Just wondering like.

[britlude]

Last time I looked (when my box went pop) it would be around £6k plus clutch... Guy in Australia does a kit.. It does get quite involved by the time you've done box, clutch, driveshaft (one is different), lever, reverse lock out mods, dash if you're doing it properly, clutch pedal and plumbing, then the option of manual cams and ecu.....

[NSXGB]

I'm sure you could get a couple of grand back in selling the old auto box and other parts to offset your outlay too, possibly increase the saleability and asking price too maybe if you came to sell?

Should be quite easy to source all the bits you require through the NSX classifieds.

[Hagasan]

One member has a spare gearbox. If you're only going 5-speed there's no reverse lockout needed. I have some spares, pedal, gear lever assembly etc. Didn't we talk about once. I can't remember what Brian at Norton Way said for labour.. £1500 I think?

[Nick Graves]

It's popular with the Prelude brigade; albeit usually a DIY & substantially cheaper.

[Kaz-kzukNA1]

I'm afraid, it's not that simple.
Without some tweaks, you won't be able to activate the spool valve and thus, the valve timing stays as the low rpm profile even above 5,800rpm. Also, you will get fuel cut at 7,000rpm instead of 7,800rpm (AT spec) and even under these conditions, there will be no CEL.

Kaz

[gturner008]

Would it not be better to sell the auto, buy a manual?

[goldtop]

Would it not be better to sell the auto, buy a manual?

Yes, in every respect. IMHO.

(I'd certainly need a lot of convincing to buy a converted car.)

[Kaz-kzukNA1]

It depends on many factors but fortunately, this was done on many AT NSX in Japan and I know some of them.

If you are about to buy the used NSX, then it would be better to find MT model from the beginning rather than wondering how the conversion was done in the past.
Also, depending on the year model, spec, etc, the price difference between AT and MT may not be big enough to justify the cost involved in the conversion. You will need to find big difference at least in the order of GBP6K – 10K to justify the cost.
Some of the prospective new owners done the home work and decided to buy the AT model and converted it to MT soon after the purchase as they found the benefit in cost in doing so rather than buying the MT model of similar year model or spec.
Also, in general, the overall condition of the AT models tend to be in better shape than the MT ones in Japan so this was one of the deciding factor.
The availability of reasonably priced used 5MT gbox was also a big factor as many 5MT owners went for the 6MT conversion in Japan.

At the same time, there were many AT owners who owned their NSX for many years and after enjoying the AT driving, started to show the interest in MT experience without replacing their very NSX and thus, the conversion menu was established in Japan.


The overall cost depends on how you source the parts and also how far you want to go.


The labour charge starts from about GBP1,500 in Japan as long as the shop knows what they are doing, running aftermarket CL Hyd line from the front to the engine bay (not using the OEM route as it's a big task) and no major modifications involved such as different final ratio, aftermarket DF, etc.


The parts is going to be the biggest factor.


Doing conversion using all used parts means you must find the donor MT NSX and this means that there was some unfortunate things happened to the donor car so you will need to inspect the conditions of the used parts.


If you are lucky, you may be able to find just the used gbox in UK/Europe that someone happens to have after converting the 5MT to 6MT spec, etc.


On the other hand, lots of newly built 6MT gbox were used for the conversion from 5MT to 6MT as well as for the AT to MT in Japan.
If you are keeping the C30A engine and not going for the C32B, then 5MT+final ratio mod could be better than using 6MT considering the torque characteristic of the C30A engine although you can't deny the light shift feeling of the 6MT with added piece of mind from the double cone synchro on all gears.

Using lightweight flywheel with OEM CL would be nice (no extra labour charge since you will need to find new/used CL any way) and depending on your preference, you may want to consider the aftermarket DF although all these mods will increase the parts as well as the labour charge.


In Japan, as a guidance, the total cost (parts + labour) starts from about GBP6K using the used gbox and over GBP10K using the newly built 6MT.
Obviously, these figures don't include any OH of used gbox, aftermarket parts or modifications.
The labour charge is similar between using 5MT or 6MT gbox so again, the biggest factor is the parts cost and any modifications.

Personally, I would recommend replacing at least the bearing and all synchro before installing the used gbox because these are fairly cheap if sourced from Japan/US and since you are going to open the gbox for this, you may want to consider OH the gbox any way.

Kaz

[Philip]

Wow, thanks for the replies guys, especially to Kaz for a thorough breakdown of what is involved. It certainly isn't worth the bother to convert to manual so I will keep my car in its standard auto format.

Phil